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From:   Shakeel Butt <shakeelb@google.com>
Date:   Mon, 4 Apr 2022 10:08:43 -0700
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Subject: Re: [PATCH resend] memcg: introduce per-memcg reclaim interface
To:     Wei Xu <weixugc@google.com>
Cc:     Johannes Weiner <hannes@cmpxchg.org>,
        Yosry Ahmed <yosryahmed@google.com>,
        Michal Hocko <mhocko@kernel.org>,
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        Greg Thelen <gthelen@google.com>
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On Fri, Apr 1, 2022 at 1:14 PM Wei Xu <weixugc@google.com> wrote:
>
[...]
>
> -EAGAIN sounds good, too.  Given that the userspace requests to
> reclaim a specified number of bytes, I think it is generally better to
> tell the userspace whether the request has been successfully
> fulfilled. Ideally, it would be even better to return how many bytes
> that have been reclaimed, though that is not easy to do through the
> cgroup interface.

What would be the challenge on returning the number of bytes reclaimed
through cgroup interface?